Okay, I think I've got it. Added 5.5 gallons of 6% bleach this evening then brushed all the sides and as much of the bottom as I could reach. SWG is off and pump set to run. I'm going to look back over the posts from my last attempt to shock and try to figure out where I went wrong. Maybe I didn't go long enough with FC at 15 and not losing any chlorine from pm till am.
Thanks.